One such hydrostatic traction drive is known for example from DE 10 2010 052 065 A1.
Hydrostats are typically controlled by a control signal for the hydraulic pump that is adjustable regarding the displacement volume thereof or the stroke volume thereof and a control signal for a hydraulic motor that is optionally variable regarding the displacement volume thereof or the volumetric displacement thereof. The control signals can be electric currents that are proportionately converted into a control pressure to which the displacement devices of the hydraulic pump and hydraulic motor are subjected, or are converted into a displacement volume.
The electric currents are manipulated in an electronic control unit depending on the operating state in order for example to prevent an overload of a diesel engine driving the hydraulic pump that is detected by means of the difference between the actual revolution rate thereof and the target revolution rate thereof.
A further known example is the ramp that is driven over during reversing, i.e. a change in direction, by means of which the electric current to the hydraulic pump and thereby the dynamics are varied and that is a function of the position of the accelerator pedal. Operating parameters of the vehicle, such as for example the revolution rate of the diesel engine and the position of the accelerator pedal, are thereby strongly related to the control of the hydrostats.
It has previously been proposed to control the hydrostats by means of a current demand that is to be fulfilled by the hydraulic motor. An overload of the diesel engine is prevented by reducing the target torque. The reversing dynamics are implemented by scaling the target torque depending on the accelerator pedal. The hydrostat control is solely focused on implementing the torque demand on the hydraulic motor.